Endangered, Invasive, and Reintroduced Species of

Pennsylvania

By: Harrison Fesel

Endangered Species

• an endangered species is a species whose numbers are so small they are at risk for extinction

• a species can be endangered because of– habitat destruction– over exploitation– disease– pollution– limited distribution

• to prevent endangerment, people preserve habitats and try to reproduce animals in captivity, and relocate them

Endangered Animals in PA

• Indiana Bats are endangered because of the destruction of there summer habitats

• Dwarf Wedge Mussels are endangered because flooding destroy their habitats

• Pink Muckets are endangered because of destruction of habitat from flooding, gravel mining, and deforestation

Indiana Bats

Dwarf Wedge Mussels

Pink Muckets

Endangered Plants in PA

• the Northeastern Bulrush is an endangered plant, because of its degrading habitat due to development and other construction

• the Small Whorled Pogonia is threatened, because of the destruction of its habitat; it is also decimated by wild pigs, and predation by deer, slugs, and vandalism

Northeastern Bulrush

Small Whorled Pogonia

Invasive Species

• a native species is a species that is present to a given area by natural process with no human intervention

• an introduced species arrives in an area due human activity either deliberate or accidental

• an invasive species is a species that is transported to an area not native to it; it reproduces, and may cause harm to the environment

Invasive Species• Invasive species are brought into the country by:

– ships- organisms are carried over by ballast water– wood products- insects can get into wood being transported– ornamental plants- some of these plants can start reproducing in the

wild– pet trade- a pet can become an invasive species when accidentally released

into the wild– deliberately- humans can intentionally introduce a species into a new

environment• Most common ways invasive species negatively affect our environments:

– preying- it can feed on native species– out-competing- can out-compete other organisms for food sources– disease- it can carry or cause diseases in an environment– preventing native species from reproducing- kill off a young species

Invasive Animals in PA• Zebra Mussel (Dreissena Polymorpha)– originated from the Caspian Sea region of Asia; they live

and feed in many different aquatic habitats; they cause problems by competing with native species, and clogging pipes

• Norway Rat (Rattus norvegicus)– originated from Europe; the rats feed on anything they can

catch or find like fish, eggs, or vegetables; furthermore they are eaten by dogs, snakes, and owls; they cause problems by carrying diseases

Zebra Mussel

Norway Rat

More Invasive Animals in PA

• Hemlock woolly adelgid (Adelges tsugae)– it originated from Japan and China; it feeds on

the phloem sap of tender hemlock shoots; causes damages by causing up to 90% mortality of the hemlock trees in the East

Hemlock Woolly Adelgid

Invasive Plants in PA• Thistle (Carduus, Cirsium, or Onopordum)– this plant is native to Eurasia; it is used as food by species

like caterpillars; highly competitive, competes with crops and forage plants

• Garlic Mustard (Alliaria petiolata)– originated in Europe; it is self fertilized, and cross-

pollinated by many insects; it is also cultivated by humans for foods, and medicine; since it grows earlier in the spring than other plants it dominates over native plant species

ThistleGarlic Mustard

Reintroduced/Extirpated Species

• reintroducing a species is when humans bring a plant or an animal species into a habitat that has modifications or has different conditions to prevent extinction

• an extirpated species is a species that is extinct in a given area

Reintroduced Species in PA

• Elk– elk were once extinct throughout most of eastern

North America– between 1913 and 1926, 177 Rocky Mountain Elk

were introduced to Pennsylvania’s forests– these new elk share a very similar niche to the

original Eastern Elk that were native to the area– in the year 2000 the elk population in PA was

estimated to be 566 individuals– the elk sometimes cause crop damage to agricultural

areas

Photos of Elk

Sources

• “National Agricultural Library”http://www.invasivespeciesinfo.gov/index.shtml

• “Invasive Species in Pennsylvania”http://www.defenders.org/resources/publications/invasives/pennsylvania.pdf

• “Pennsylvania’s Elk Herd Growing” http://www.mhhe.com/biosci/pae/es_map/articles/article_66.mhtml

• “National Wildlife Federation” http://www.nwf.org/Wildlife/Wildlife-Conservation/Threats-to-Wildlife/Invasive-Species.aspx